The long term objective of this study is to demonstrate that children and adolescents who develop schizophrenia show specific neuropsychological, anatomic and physiologic abnormalities prior to or coincident with the onset of schizophrenia that are related etiologically to the development of the disorder. An increasing number of studies find abnormal brain structure and function in adult schizophrenics. Frequently it is suggested that these changes are present before the onset of the schizophrenic disorder and may be present prenatally or in early childhood. Few studies have examined brain structure and function longitudinally in children with early onset schizophrenia or at high risk for developing schizophrenia to determine if these changes are in fact present. Subjects in this study will be 60 children who range in age from 6 to 16. Thirty subjects classified as having a schizophrenia spectrum disorder, and 30 controls based on structured interviews, DSM III-R criteria and standardized rating scales will be matched for age, sex, SES and handedness. They will undergo a battery of neuropsychologic tests to assess general as well as frontal and temporal lobe functioning and will be studied with high resolution Magnetic Resonance Imaging (MRI). MRI is ideally suited to study brain structure, physiology and development in children due to its high contrast resolution and absence of known biological hazards at currently used field strengths. The Center for Non- Invasive Diagnosis at the University of New Mexico is currently a leader in the field of MRI. The use of MRI in this protocol provides an unprecidented opportunity to study neurodevelopmental features of schizophrenia in children. Morphometric measurements of specific brain areas (ventricle size, anatomic asymmetries, and size of frontal and mesial temporal limbic structures) will be obtained from MRI scans. Values will be compared with neuropsychological tests for specific diagnostic groups and controls at baseline and at follow up three years later. The combination of these techniques in the study of children with schizophrenia spectrum disorders over time will yield important information about developmental neuropathology in schizophrenic disorders.